Baghdad, Iraq (CNN) -- At least five Iraqis were killed and at least 18 others were wounded in a suicide bombing at an Iraqi army checkpoint in western Baghdad Friday morning, the Interior Ministry said.

Three of the people killed and two of the people wounded were soldiers, the ministry said. The others were civilians.

The attack at a checkpoint in Baghdad's Ghazaliya neighborhood comes after a wave of violence that killed and wounded hundreds of Shiite pilgrims during an annual pilgrimage that concluded on Thursday.

At least 66 pilgrims were killed and nearly 400 wounded in violence targeting them across the capital.

Iraq is facing political uncertainty more than four months after the country's inconclusive national elections.

U.S. and Iraqi officials have expressed concerns that insurgents would take advantage of the political vacuum in an attempt to reignite the sectarian warfare that gripped the country for years.

Overall violence in Iraq has dropped drastically over the past two years compared to the height of sectarian warfare in 2006 and 2007, but such attacks do continue.

The country is at a critical period as U.S. forces continue drawing down troops from the current 77,000 to reach 50,000 at the end of August ahead of the Obama administration's deadline to end America's combat missions by September 1.

According to the security agreement between the United States and Iraq, all American forces are scheduled to leave the country by the end of next year.